Hydraulic dredge ladder



Sept. 11, 1956 L. BELL 2,762,136

HYDRAULIC DREDGE LADDER Filed Jan. 2, 1953 7 Sheets-Sheet 1 Le'roy BellINVENTOR.

BY anyway 153M5 7 Sheets-Sheet 2 Leoy Bell INVENTOR.

L. BELL HYDRAULIC DREDGE LADDER HMMH m WH I IM MHHI ww i l l I HUMlllll-ll'lllll l/ll-l ll l||..|I..||lI.|||||||.l.|I|.I.I|l-|l| [III IIISept. 11, 1956 Filed Jan. 2, 1953 Sept. 11, 1956 L. BELL 2,762,136

HYDRAULIC DREDGE LADDER Filed Jan. 2, 1953 7 Sheets-Sheet 3 L eroy BellINVENTOR.

WW @Mgg Sept. 11, 1956 BELL 2,762,136

HYDRAULIC DREDGE LADDER Filed Jan. 2, 1955 7 Sheets-Sheet 4 Fig. 4

I Leroy Be ,2 INVENTOR.

BY WW m Sept. 11, 1956 L. BELL 2,762,136

HYDRAULIC DREDGE LADDER Filed Jan. 2, 1953 7 Sheets-Sheet 5 F l" g. 5 24o 172 72 5a 4 104 F g. 7

o 0 so -lae /70 o /02 u //0 1/0 I l Lero y Bell 84 INVENTOR.

WW EM Sept. 11, 1956 BELL HYDRAULIC DREDGE LADDER 7 Sheets-Sheet 7 FiledJan. 2, 1955 Leroy Be/l INVENTOR.

BY flaw/ 16M 0 H m 0 a F 0 42 8 m. W h 0 4 9 2 I 2 w 4 and United StatesHYDRAULIC DREDGE LADDER Leroy Bell, Fort Lauderdale, Fla.

Application January 2, 1953, Serial No. 329,213

2 Claims. (CI. 37-67) This invention relates in general to dredges, andmore specifically to a hydraulic dredge ladder construction.

At the present time, the hydraulic dredges in use consist of a dredgehull which has mounted at the forward end thereof an A-frame from whichextends forwardly a hydraulic ladder. The hydraulic ladder is supportedat its rear end by the A-frame and during a cutting operation, the outerend thereof is primarily supported by a cutter head of the same. Thisarrangement is disadvantageous inasmuch as the entire weight of thedredge ladder may not be placed on the cutter head to facilitate thecutting of rock and the like, the dredge ladder extends forwardly fromthe supporting A-frame with the result that a cantilever action takesplace when the dredge hull is swung during a dredging operation byswinging cables attached to the dredge hull, and the arrangement of thecutter head on conventional dredge ladders is such that the cutter headcuts only when the dredge is being swung in one direction. tI istherefore the primary object of this invention to provide an improvedhydraulic dredge ladder arrangement which will overcome all of the abovementioned disadvantageous features.

Another object of this invention is to provide an improved hydraulicdredge ladder construction which includes a vertical A-frame mounted atthe forward end of a dredge hull and being constructed to have a dredgeladder movable vertically therethrough, a dredge ladder mounted withinthe A-frame for vertical movement whereby the entire weight of thedredge ladder may be placed directly upon cutter heads carried thereby.

Another object of this invention is to provide an improved hydraulicdredge ladder construction in which the dredge ladder remainssubstantially within the confines of the dredge hull and to whichswinging cables are connected whereby side thrust is imparted directlyto the dredge ladder adjacent the cutter head thereof so as to eliminatebending and other stresses in the dredge ladder and its associatedsupport.

Another object of this invention is to provide an improved dredge ladderwhich may be lifted vertically through a well in the dredge hull, saiddredge ladder and said well being so arranged whereby the cutter headcarried by the dredge ladder may be raised up onto the confines of thedredge hull within said well so that the dredge hull maybe floated intoposition.

A further object of this invention is toprovide an improved hydraulicdredge ladder construction which ineludes first and second cutter heads,said cutter heads being designed to rotate in opposite directions soasto cut when the dredge is being swung in opposite, direc-' tions, saidcutter heads permitting a dredging action regardless of the direction inwhich the dredge is being swung.

A still further object of this invention is to provide an improveddredge ladder construction which includes a support and a verticallyadjustable dredge ladder, said support and dredge ladder havingassociated therewith a vertically movable guiding framework which istelescoped over the dredge ladder and which is positionable within theconfines of a well in a dredge hull through which the dredge ladderpasses in order to properly support the dredge ladder against transversemovement.

These together with other objects and advantages which will becomesubsequently apparentreside in the details of construction and operationas more fully here: inafter described and claimed, reference being hadto the accompanying drawings forming a part hereof, where in likereference numerals refer to like parts throughout, and in which:

Figure 1 is a top plan view of a hydraulic dredge and shows the generalarrangement of the improved dredge ladder construction, other portionsof the hydraulic dredge being shown in schematic;

Figure 2 is a side elevational view of the dredge of Figure l and showsthe dredge ladder in a lowered position with the cutter head thereof inthe middle of a dredging operation, a portion of the dredge hull beingbroken away and shown in section in order to clearly illustrate auniversal joint of suction piping, an intermediate portion of asupporting frame for the dredge ladder being omitted;

Figure 3 is a front elevational view of the hydraulic dredge of Figure land clearly shows the details of the improved hydraulic ladder and itstwo cutter heads, also shown is the relationship between the hydraulicladder and its associated supporting frame, an intermediate portion ofthe supporting frame being omitted;

Figure 4 is a front elevational view similar to Figure 3 and shows thedredge ladder in its uppermost position within its supporting frame topermit movement of the hydraulic dredge from one place to anotherthrough relatively shallow water;

Figure 5 is an enlarged fragmentary transverse vertical sectional viewtaken through the lower portion of the dredge ladder and shows itsgeneral construction and the relationship of the same to the dredge hullwhen it is in its uppermost position;

Figure 6 is a fragmentary transverse horizontal sectional view takensubstantially upon the plane indicated by the section line 6-6 of Figure5 and shows the general cross-section of the hydraulic ladder and acentral portion of its supporting frame;

Figure 7 is a schematic diagram of the means for controlling a dredgingoperation of the hydraulic dredge of Figure 1;

Figure 8 is a fragmentary vertical sectional view taken through thedredge ladder in the vicinity of the dredge hull when the dredge ladderis in a lowered position and shows the relationship of a verticallymovable supporting framework telescoped over'the dredge ladder forsupporting the lower portion thereof within hull through which thedredge ladder extends;

Figure 9 is an enlarged fragmentary vertical sectional view takensubstantially upon the plane indicated by the section line 9-9 of Figure6 and shows the general construction of a rear portion of one of thecutter heads and .the arrangement of suction piping connected to theReferring now to the drawings in detail, it will be.

seen that there is illustrated a hydraulic dredge which Patented Sept.11, 1956 a well in the dredgesame is in a raised poisreferred to ingeneral bythe reference numeral 10 and which includes a dredge hall- 12;dredgehnlt 12 has the general configuration of conventional dredge hullswith the exception that the forward end of the sameis provided with anenlarged well l 'which' is best" illustrated in Fi-gure Communicatingwith the large well 114 at the rear end" thereof'is a centrally"l'ocated' smaller well 16 whose purpose will" beset fbrtlr more detailhereinafter.

Rigidiy: secured to: the front portiinn of' the" dredge hull 125 andextending npwmdlytherefrom in overlying relation! to the well" I4 is: asupporting frame which is of thc -A-Nframe type and which: isreferred toingeneral byrtheg, reference numeral The supporting; frame 1% includes apair of identical halves which are referredftoin: generazlf bythereference numeral 28 and which, are joined together at their upper endsby transverse frame mernbersrZZL Each of the, frame'halveszh includes apair of longitudinally spaced angle members 24" which fornn the mainframe members of the" frame halves 2i! and which alsofunction asguidemembers for a-d'redge ladder which iscarr-ied by the supportingframe-18; the' dredge-itladder being referred to in general by thereferencenurneral: 25 and will be described in more detail hereinafter:

Each;frameihalf 2t)= also* includes' a pair of diagonal frame members 28which slope upwardly and inwardly 251-2 adjacent thesupper' ends Ithereof; The: lower'endsof the; diagonal frame members-28 are I securedto the lower ends; of the angle members 241 by a horizontalframemenrher: itlzanda supporting gussetconstruction 32. It will beunderstood that. the; horizontal frame: member 30 lies; directly; on-thedeck of the dredge. hull: 1-2'. and is rigidlyasecuredi tonthetdredge;hull'to support the: associated ,anglea' member 24 in' cantileverrelation overlying the well 14.. Also. connecting together the angle:meme hers '24 and their associated diagonal frame. members 28::arcdiagonal braces 34? and longitudinal bracing13'6, the. longitudinalbracingav being best: illustrated in Fig-- meal The;dredge ladder; 26 isgenerally rectangular int cross, section and is formed by front andICfli'Pfiil'S-OfVfiHiCfll f time:menzthersE 318; and: 40;respectively-,: which aretinmthe form; (If-(angle;- members:internesterlwithin angle; members: 24, sagas: to be guided "therebyfOIflVBI'fiCfilZ movee mental Connecting? together: the front; verticahframe members 38 at verticallyispaced:interyals arefiontnhoria zontal'frame: members. 42: which: haves disposedtherehetween.diagonal:,bracing{44=. The rear: vertical frame,- members 40 are alsoconnected together by similar'rhorieznntalframesmembers;46:and;diagonal, bracing 48;

The: dredge ladder 26.- also includes. horizontal: side;framermembersisuwhich conneeti'together; adjacentz front and: rear;vertical-frame mernhers 38: and; 4h... Intercomnecting; vertically,spaced; side frame members 50; are diagonal: braces 52. V 1

Carried by uppermost horizontalframwmembers 42:5 and; 46 areilongitudinallg aligned; padreyes; 54-, whiohhave connected, thereto:lower; ends; of". lifting; bars 56". The:

. upper; ends; of the liftingbars 56; are connected: teat book; of; a.traveling block ;5 8,"WhiCht iS connected: by=-an:.

V and' which are secured to theirre spective angle-members ber 78 isal'scr'bracect intermediate its endsby' depending vertical framemembers. 801* which are. secured to the lowermost front horizontal framemember 42.

Carried at-the lower end" of 'the-dredge ladder Z6 and supported by thetransverse: frame: members 74 and 78 are cutter heads 82 and 84.Referring now to Figure 5 in particulan'it is seen that the two cutterheads 82 and 84 are identical, with the exception that their individualcutting blades 86 and 88, respectively, are curved V in difierentdirections and" are designed to cut" effectively wherr'the' cutter heads82 and'84 'are rotated im opposite directions. The purpose of thedifference in the blading ofthe two' cutter heads will be explained moredetail hereinafter. V I

Inasmuch as'the two cutter heads82 and 8'4 are identical except forthearrangement oftheir' blades; only one: of the cutter'head's, thecutter'head 84- will be ex,

pl'ained in detail. Ae is best illustrated in Figure 1 0;

- the-cutter head 84 includes a rear main cutter 9'0 =a'nd'-" a=forward-auxiliarycutter 92; The rear main cutter 90 includes alongitudinallyextending snpporting shaft 94 which is-rot'ataoly jour-naled in suitable pillow blocks Vdetachablysecured to the lowersideof the transverseframe members 78' and 8tlg. the pillow blocksecuredtothe transverse: frame member 78 not being tillustratedi The main cutter90,- whi'ch is'-* disposed between the transverse frame'members-fi and78; includes a plurality of 'longitudinally extending blade support's 98whichare secured to the shaft 9 wby a: plurality of longitudinallyspaced spokes 96; It: will benoted' that the spokes 96 are disposed onlyin the-forward halfofi the maincutter' 905 Carried by the blade supports98-"are' suitabl'e spiral cutter blades" 88 which have been: described'in more} 7 detail abovea elongated: cable: fitlt'o; a crown: block:62.=The crowns.

blQCks 62-. is, suspended; frorrrv a cross beam: 64lrestingr: upomandsecured tozvuppenhorizontalg; side: frame members 66 which connecttogether: the: uppenendss otfthei angle: members. 24 of; each. frame;half; 20; A, free end otgathei ble 6D; extends-into; at deck: 1191156268of: the; hydraulic dredge 10 and is reeledupoma drumz'lflrofr ae 7adiacentrtheir lowen endsiis anenlargedgtransverscftame 4 member 74. Thetransverse frame member 74 is bracedby: arpair of Vintermediatesyertical' frame members; 76

In: order that the maimcutter may be 'conveniently rotated; there; hasbeen 1 rigidly: secured to the rearrpon- V tionst of fll'ei bladesupports 98*. a i drive :pulley 1 00'.- The driive: pulley 100 has:entrainedi there'oven afi drilve' chain 7 102 ,whosez-uppen end:. is;entrained: over a: driver pulleyra 10.45which:is-carriedtbya:.driveishaft of azreductioni gear box :'1=06:. The: reduction gear:130x106 upwardly? conr nectedtt'o arpower'source'gasuchz as an internallcombuse tio'n: engine?v 108; the: reduction gear box-1' lofiiand that:interna-licombustion: engine 108 being; supported: hyt: uppermostzfiamemembersrotthetdredgesladden'lflt as; the drivespulley 100.isrdisposed;.slightl3a outawardly of the confines of? the-idredgecladder 26;: there:

is-tcarriedxhy an associated: lowermost side-frame: memben'50' an idler:pulley: 110:1 As iszbestill'ust'ratedrimn Figured} the: idler pulleytill-urges the: dr'iverchaimim wardly; as: it: comes; ofi-.its-'vassociated: drive? pulley- 100,:- 50: as to: he: disposed.- within:thccconfines. oiiiithe; dredge laddenz2fizi The forward end of thezshaft9451's reducedzandpolygsonal;in:crossasection:;aseat:11%ldigidlyimounteda on the.

'rediuiedr:portionv 1 121 of: the:- shaft 9.4 f0fi rotation thercs=-witlriis a hubi 1 14;. therhub 1 1345 being-secured OlIiIhBS reef duc'edportionmf th'e shaft- 112 by a locking member H6:

The huh 114% is part; of the:auxiliary"cutter 92 andlhas suppcartetlthereby:spirahcutter blades- 118a i Secured tattle-front face ofthe transverseeframetmema V rearplate 120 which encloses theupper porti"nto'fi the main: cutter 905 Extending": into the; lower ber 74 in amanner best illustratedvin Figure 10 the 1 main cutter; 90 rearwardlyoffihe rearmostsmkbx-QSL is a suction inlet-pipe ltkz whicht-issupportta'dihy; renter able yokes 124 and 126 secured to the bottom andrear of the transverse frame member 74, respectively. Carried by theinlet suction pipe 122 and closing the bottom portion of the rear of themain cutter 90 is a lower plate 128 which has passing therethrough theinlet suction pipe 122.

Referring now to Figures and 6 in particular, it is seen that each ofthe inlet suction pipes 122 includes a horizontally disposed section 130together with a vertical suction pipe 132 to form a Y- fitting. .Whilethe yoke 126 does aid in the support of the suction inlet fittings 122,it will be noted that it is actually connected to the suction pipe 132for retaining the same in a vertical position.

Referring now to Figures 1 and 2 in particular, it will be seen thatmounted within the deck house 68 is a suitable rotary pump 136 which isprovided with an inlet 138. The inlet 138 is connected by a universaljoint 140 to a first generally horizontal suction pipe 142. Telescopedwithin the first horizontal suction pipe 142 is a second horizontalsuction pipe 144. The second horizontal suction pipe 144 is connected bya universal fitting 146 to an L-shaped upper end of a vertical suctionpipe 148. The Vertical suction pipe 148 is connected by a plurality ofintermediate telescope vertical suction pipes 150 to the suction pipe132. The rotary pump 136 also includes a discharge pipe 152 which may beconnected to suitable discharge pipes 54 which extend over the stern ofthe dredge hull 12 and may either lead to the shore or other points 'ofdischarge.

When it is desired to elevate the dredge ladder 26 so that the cutterheads 82 and 84 thereof are disposed within the well 14, it will be seenthat it will be necessary to telescope the suction pipes 148, 150 and132. Inasmuch as the length of the pipes when extended, as compared totheir combined length when telescoped, is by construction greater thanthat of the extended length of the dredge ladder 26 as compared to itselevated projectmg length, it will be seen that it is necessary for theupper suction pipe 148 to be elevated in order that the dredge ladder 26may be elevated to its uppermost position. In order to assure verticalmovement of the upper suction pipe 148, it is connected to a suitableguide way 156 carried by the rear portion of the supporting frame 18.Vertical movement of the upper vertical suction pipe 148 necessitatesthe universal fittings 140 and 146 as well as the telescoping suctionpipes 142 and 144.

As is best illustrated in Figures 1 and 7, the hydraulic dredge has alsomounted in its deck house 68 a pair of winches 158 and 168 which includedrums 162 and 164. The drums 162 and 164 have reeled thereon ends ofswinging cables 166 and 168, respectively. The swinging cables 166 and168 extend from the opposite sides of the hydraulic dredge 10 and havetheir other ends anchored to suitable dolphins 170 and the like. I

The swinging cables 168 and 170 extend upwardly from their respectivedrums 162 and 164 and are entrained over suitable sheaves 172 carried byan upper rear portion of the supporting frame 18. The cables 166 and 168then pass downwardly through the supporting frame 18 and the dredgeladder 24 and are entrained over lower sheaves 174 carried by the rearvertical frame members 49 adjacent the lower ends thereof.

Inasmuch as it may be undesirable to disengage the cables 166 and 168from their respective sheaves 174 while moving the hydraulic dredge 10,the dredge hull 12 has been provided with suitable recesses 176 in thebottom and inner side portions thereof adjacent the well 14. The upperportions of the recesses 176 include curved plates 178 over which thecables 166 and 168 pass to facilitate sliding of the same.

In the normal operation of a hydraulic dredge, one of the swingingcables will be payed out while the other is taken in at the same rate.This causes the swinging of which are connected the entire hydraulicdredge in one direction. Inasmuch as the cutting blades of the cutterhead of the hydraulic dredge should be drawn into the material beingdredged, and since a cutter head can only cut in one direction, it willbe seen that during a dredging operation with a conventional dredge thatthe dredging will be done in one direction only. This results in a lossof time by reversing the paying out and taking in of the cables to swingthe dredge in an opposite direction to start the dredging operationover.

In the present hydraulic dredge, the hydraulic dredge 18, the provisionof two cutter heads 82 and 84 which are designed to rotate in oppositedirections permit the hydraulic dredge 16 to perform a dredgingoperation regardless of the direction in which it is being swung. Whenthe hydraulic dredge 10 is swung to the right, as viewed in Figure l,the cutter head 82 engages the material to be moved and the same isdrawn rearwardly through its associated inlet suction pipe 122 due tothe action of the rotary pump 136. During this time the swinging cable168 is being taken in while the swinging cable 166 is being payed out.When the end of the cut is reached, the dredge ladder 26 is lowered thedesired depth through the use of the winch 70. The cutter head 82 isthen stopped and the cutter head 84 is rotated simultaneously with thetaking in of the swinging cable 166 and the paying out of the swingingcable 168. In order that material cut by the cutter head 84 may be drawninto the rotary pump 136, a valve 180, which is best illustrated inFigure 9, controlling the flow of material into the lower verticalsuction pipe 132 from the pipes has its posiinlet suction pipe 122' tionreversed to communicate the of the cutter head 84 with the rotary pump136.

Inasmuch as the cutter heads 82 and 84 extend outwardly of the confinesof the dredge ladder 26, it will be seen that the well 14 has a widthgreater than the width of the dredge ladder 26 to provide clearance forthe cutter heads 82 and 84. In order that the dredge ladder 26 may besupported against bending movement at the extreme bottom of the dredgehull 12, there is provided a framework which is referred to in generalby the reference numeral 182 at each side of the dredge ladder 26 andthe sides of the well 14. Each framework 182 includes a vertical guidemember 184 disposed adjacent the front and rear corners of the dredgeladder 26 at its respective side. The vertical guide members 184 of eachframework 182 are connected by a horizontal member 186. It will be notedthat each of the guide members 184 includes a vertical guide way 187, inwhich is disposed a vertical guide member 188 carried by an adjacentside of the well 14 and projecting inwardly thereof. It will be seenthat the guide members 188 guide the frameworks 182 in their verticalmovement.

When the dredge ladder 26 is in a lowered position, as is bestillustrated in Figure 8, the frameworks 182 are disposed adjacent thebottom of the dredge hull 14 and are suspended from cables 190 connectedto eyes 192 carried by the angle members 24 of the supporting frame 18.However, when the dredge ladder 26 is in its uppermost position, as isbest illustrated in Figure 9, the frameworks 182 are raised upwardly outof the Well 14 to provide clearance for the cutter heads 82 and 84. Inorder that the frameworks 182 may be moved upwardly upon upward movementof the bottom of the dredge ladder 26 into the well 14, there is carriedby the vertical frame members 38 and 40 adjacent their lower endsoutwardly projecting stop members 194. The stop members 194 engagebeneath each of the vertical guide members 184 and urge the frameworks182 upwardly to the positions best illustrated in Figure 9. Thus, itwill be seen that the dredge ladder 26 may be supported the full depthof the dredge hull 12, and at the same time, there will be providedsufiicient clearance for the cutter heads 82 and 84 of the dredgeladder.

Referring now to Figure 6 in particular, it will be seen the full?weight of the? dredge: ladder maybe pl'a'ced'upon the cutter h'eadsi oftthe: same to: provide more efiicient cutting. Also, it will be seen thatthe swinging cablesof: the: hydraulic dredge" are; connected directly tothe dredge ladder adjacent its lowerend: s'othat thesideward thrustuponthe cutten heads: will be imposed almost directly at theinpoihtsofiisupport so as t'o eliminate bending StIGSSCSiiE-thfi' dredge la'dderother than those imposed' by: resistance of the? dredgehulli tosideward' movement througlr the: water; Also byproviding two cutterheads instead: of the customaryr one;-.it=-is seen that a dredgingoperation may be=.continued1 regardless of the direction inwhich: thedredgeis beingswungi In the actual operationrof one of the cutter heads,the auxiliary: cutter. 921thereofwill penetrate the deepest into arock;or thelike formationiand-urgeparticles of the same back-to the maincutter 9,0 which operates in anormal manner, hollow center willthensuction pipe 122 direchthecuttings into the inlet rock; formation, it-Wlll be seentthat no rock will be cut inthe space between the maincutter90 and the auxiliary cutteru92.- Inasmuch 'as this rock would be engagedby one of the front vertical: frame: members 38, it will be seen that inthe caseof aerelatively soft rock, the-front vertical'frame member willcause the narrow portion of rocks left between t the 1 two cutters tobreakofiand pass into themain cutter 90iv However, inrthecase ofextremely hard rocks, the pressure exerted by the 'front frame memtion,Inithis case, it=mayj be necessary to provide outwardlyprojecting-teeth(not shown)- on the front vertical frame. member to causerasliftingaction upon the rock formation to break the: same up; 7 g It will beunderstood that the controls for the improvedhydraulic dredge whichhas:been? disclosed above' will be substantially,

and only minor changes willrbe? necessary in' hydraulic those skilledintthe art it isnot desired to limit the inventiont to the;exact.constructionshown and described,

Theim'ain cutter 90,1which is provided with a the sameast thatof tconventional dredges and accordingly, all suitablenrodifications andequivalents may be=resorted tOZiaIling-Within the' scope of the appendedclaimst r .v I 1 What: is: claimed: as new is as follows:

a l. A hydraulic dredge comprising a dredge hull, a dredge laddermountedat one end of said dredge' h'ulL-a' cutter he'ad'at' the lower end of 1said dredge ladder,- s'a'id ladder extendingivertically, said' ladderpassing through anopen well: in saiddredg'e hull, a: frameworktelescoped' over saidtdredg'e ladder positioning sai'd dredge ladderWithin Said we'll, saidladder being-.mount'edin z'i vertical 1 framecarried by said dredge hull, said framework-beingii v suspended fromsaid'vertical flame, stop means on said dredge ladder with saidframework-man'upperposition of. said 'dredge la'dder fdrelevating saidframework with said dredge ladder.- n 1- Q 2,. A hydraulic dredgecomprising a dredge hull; a dredge ladder mounted: at one end-of saiddredge hull, a-

cutterhead} supported by the lower end of said dredgeladder, saidladderextendingvertically, a-w'ell in said dredge hullopening through oneend.- of said dredge hull,-

associated therewith." In the case of a said ladder passing-tthrough-said open well; a framework telescoped overs'aid dred-geladdenpositioning said dredge" ladder within said wella vertical framecarried by said 1 dredge hull, said ladder: being? mountedin's'aidverticalfra-rne,.said framework being suspended fromsaid vertical frame,stop meanson-"said dredge'ladder engaging said framework in an'upperposition of said dredge ladder for elevating said framework with saiddredge} ladder; means for vertically adjus ingesaid drcdgeladder, pumpmeans? carried by saiddredge hull tsuction piping== connectingsaidfpurnp means to; said cutterhead, said pipingincluding"e verticallytelescoping-r sections extending within said-.7

ladder, a-lowermost of said sectionsbeingqigidly secured to saidcutterhead, an-uppermostofi saidsections'being guidingly, connectedtosaidvertical'frame.

' References Cited-in the-file of this patent" UnrranfsrATEs' PATENTS185,600 Von-Schmidt" Dec. 19', 187 6 328,09 5- Wa1sh- Oct. 13, 1885" 3552-51 Bowers Dec. 28, 1886 401,896 McFarlane Apr. 23,:1889-1 477,82]Southen. June 28; 1892 601 524 7 Parker Mar. 29, 1898" 629,910 NicholsAug. 1; 1899" 735,255 r Gillespie Mar. 28;1905 1 992 692 Newman Sept.-5, 19-11 1,0- 19 ;6 1 0; Donnelly 19-12.- .6; 9.; Cas y 1,713,037 Ellis

